Folinic Acid to Prevent Pemetrexed-Associated Neutropenia After Intrathecal Administration: A Quick Win

With interest we read the article of Fan et al. 1 Fan C. Zhao Q. Li L. et al. Efficacy and safety of intrathecal pemetrexed combined with dexamethasone for treating tyrosine kinase inhibitor-failed leptomeningeal metastases from EGFR-mutant NSCLC—a prospective, open-label, single-arm phase 1/2 clinical trial (unique identifier: ChiCTR1800016615). J Thorac Oncol. 2021; 16: 1359-1368 Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar in which the efficacy and safety of intrathecal pemetrexed (IP) for treatment of leptomeningeal metastases in patients with EGFR-mutated NSCLC were investigated. Clinical response rate was promising (84.6%), but despite folic acid and vitamin B supplementation, the incidence of myelosuppression was high (any grade 36.7%, grades III–IV 16.7%). These percentages are in line with other studies evaluating IP. 2 Li H. Zheng S. Lin Y. et al. Safety, pharmacokinetic and clinical activity of intrathecal chemotherapy with pemetrexed via the Ommaya reservoir for leptomeningeal metastases from lung adenocarcinoma: a prospective phase I study. Clin Lung Cancer. 2023; 24: e94-e104 Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar , 3 Pan Z. Yang G. He H. et al. Intrathecal pemetrexed combined with involved-field radiotherapy as a first-line intra-CSF therapy for leptomeningeal metastases from solid tumors: a phase I/II study. Ther Adv Med Oncol. 2020; 121758835920937953 Crossref Scopus (16) Google Scholar , 4 Miao Q. Zheng X. Zhang L. Jiang K. Wu B. Lin G. Multiple combination therapy based on intrathecal pemetrexed in non-small cell lung cancer patients with refractory leptomeningeal metastasis. Ann Palliat Med. 2020; 9: 4233-4245 Crossref PubMed Scopus (7) Google Scholar We suggest an easy-to-implement strategy to overcome myelosuppression: oral folinic acid (FA) rescue therapy on top of routine vitamin supplementation. Efficacy and Safety of Intrathecal Pemetrexed Combined With Dexamethasone for Treating Tyrosine Kinase Inhibitor-Failed Leptomeningeal Metastases From EGFR-Mutant NSCLC—a Prospective, Open-Label, Single-Arm Phase 1/2 Clinical Trial (Unique Identifier: ChiCTR1800016615)Journal of Thoracic OncologyVol. 16Issue 8PreviewWe aimed to evaluate the efficacy and safety of intrathecal pemetrexed (IP) for treating EGFR-mutant leptomeningeal metastases (LMs) from EGFR-mutant NSCLC. Full-Text PDF Open Archive